Adding a second Zimbra account fails to Desktop

When I set up Zimbra desktop on my MacBookPro (intel), running OS X 10.5.6 with 3 GIGs of RAM, my main account loaded fine. I also have a second Zimbra account I use for a sales list and I get this error when I try and add it. We have an internally hosted Zimbra machine running the enterprise version. It should be up to date...

When I set up Zimbra desktop on my MacBookPro (intel), running OS X 10.5.6 with 3 GIGs of RAM, my main account loaded fine. I also have a second Zimbra account I use for a sales list and I get this error when I try and add it. We have an internally hosted Zimbra machine running the enterprise version. It should be up to date...

When I set up Zimbra desktop on my MacBookPro (intel), running OS X 10.5.6 with 3 GIGs of RAM, my main account loaded fine. I also have a second Zimbra account I use for a sales list and I get this error when I try and add it. We have an internally hosted Zimbra machine running the enterprise version. It should be up to date...